SIMULATION AND STRUCTURAL ANALYSIS OF FLYWHEEL USED IN 50 TON POWER PRESS

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1 SIMULATION AND STRUCTURAL ANALYSIS OF FLYWHEEL USED IN 50 TON POWER PRESS Shila S. Chaudhari 1, Prof. T. D. Garse 1 M.E.Scholar, J.T. Mahajan C.O. E., Faizpur (India), 2 Assistant Professor, J.T. Mahajan C.O. E. Faizpur, (India) ABSTRACT In this thesis we are studying various profiles of flywheel and the stored kinetic energy is calculated for the respective flywheel.various profiles designed are solid disk, disk rim, webbed/section cut, arm/spoke flywheel. It shows that smart design of flywheel geometry could both have a significant effect on the Specific Energy performance and reduce the operational loads exerted on the shaft/bearings due to reduced mass at high rotational speeds. Efficient flywheel design used to maximize the inertia of moment for minimum material used and guarantee high reliability and long life. FE analysis is carried out loading on the flywheel and maximum von mises stresses and total deformation are determined. A flywheel is the heavy rotating mass which is placed between the power source and the driven machine to act as a reservoir of energy. It is used to store the energy when the demand of energy of energy is less and deliver it when the demand of energy is high. The current thesis is focused on the analytical design of arm type of flywheel which is used for power press operation. Now in regard to the design of flywheel it is required to decide the mean diameter of the flywheel rim, which depends upon two factors such as availability of space and the limiting value of peripheral velocity of the fly wheel. However the current design problem is formulated for power press machine which has to be perform the various operations and space limitation that is the diameter of flywheel should not exceed 790 mm, hence it can be observed that the design of the flywheel is to be carried out (based) on the reduction ratio of motor and flywheel and accordingly the fluctuation of energy, dimensions of the flywheel, stresses induced in the flywheel are determined. Finally after detail analysis it is observed that the induced diameter of the flywheel is less than the allowable/permissible diameter and hence it can be concluded that the design is safe from operational features. I INTRODUCTION A flywheel is a mechanical device with a significant moment of inertia used as a storage device for rotational energy. Flywheels resist changes in their rotational speed, which helps steady the rotation of the shaft when a fluctuating torque is exerted on it by its power source. Flywheels have become the subject of extensive research as power storage devices for uses in machines. Flywheel energy storage systems are considered to be an attractive alternative to electrical energy due to higher stored energy density, higher life term, and deterministic state of charge and ecologically clean nature. 50 P a g e

2 A flywheel acts as an energy reservoir, which stores energy during the period when the supply of energy is more than the requirement and releases energy during the period when the requirement is more than the supply. The energy-storage capacity of a flywheel is determined from its polar moment of inertia J and its maximum safe running speed. The necessary inertia depends on the cyclic torque variation and the allowable speed variation or, in the case of energy storage flywheels, the maximum energy requirements. The safe running speed depends on the geometry and material properties of the flywheel. The function of flywheel are as follows, 1. To store & release energy when needed during the work cycle. 2. To reduce the power capacity of the electric motor or engine. 3. To reduce the amplitude of speed fluctuations. II LITERATURE SURVEY Literature review is an assignment which gives idea about previous work done by different authors & from the research paper published by them in different journals gives the data about there research work which are helpful in our project. It gives the guideline or path for progressing our task.earlier many authors work on same. So we are collecting some useful information for our project. For designing the flywheel following parameters has taken into consideration by reviewing literature review. SushamaG.bawane, A.P.Ninawe,&S.K.Choudhary [1] had proposed flywheel design.they study different types of flywheel & use different types of material for the analysis purpose.by using FEA analysis suggested the best material for the flywheel. S. M. Dhengle Dr. D. V. Bhope, S. D. Khamankar, [2] shows the comparison between analytical stresses and FE stresses in Rim by varying no. of arms& comparison between FE stresses on arm and analytical calculated bending stresses in arms. They also seen that as a number of arms increases from 4 to 8, the stresses in the arms goes on reducing. This may be due to sharing of load by larger no. of arms shows the comparison of FE stresses and analytical bending stresses near the hub end of arm for 4, 6 and 8 arms flywheel under the influence of tangential forces on rim. Bjorn Bolund, Hans Bernhoff, Mats LeijonThe early models where purely mechanical consisting of only a stonewheel attached to an axle. Nowadays flywheels are complexconstructions where energy is stored mechanically and transferred to and from the flywheel by an integrated motor/generator. The stone wheel has been replaced by a steel or composite. Rotor and magnetic bearings have been introduced. Today flywheels are used as supplementary UPS storage at several industries world over. Future applications span a wide range including electric vehicles, intermediate storage for renewable energy generation and direct grid applications from power quality issues to offering an alternative to strengthening transmission. One of the key issues for viable flywheel construction is a high overall efficiency, hence a reduction of the total losses. The predominant part of prior studies has been directed towards optimizing mechanical issues whereas the electro technical part now seems to show great potential for 51 P a g e

3 improvement. An overview of flywheel technology and previous projects are presented and moreover a 200kW flywheel using high voltage technology is simulated. [2] SudiptaSaha, Abhik Bose, G. SaiTejesh, S.P. Srikanth the performance of a flywheel can be attributed to three factors, i.e., material strength, geometry (cross-section) and rotational speed. While material strength directly determines kinetic energy level that could be produced safely combined (coupled) with rotor speed, this study solely focuses on exploring the effects of flywheel geometry on its energy storage/deliver capability per unit mass, further defined as Specific Energy. Proposed Computer aided analysis and optimization procedure results show that smart design of flywheel geometry could both have a significant effect on the Specific Energy performance and reduce the operational loads exerted on the Shaft/bearings due to reduced mass at high rotational speeds. This paper specifically studies the most common five different geometries (i.e., straight/concave or convex shaped2d). [3] M.lavakumar, R.prasannasrinivasThis paperinvolves the design and analysis of flywheel to minimize the fluctuation in torque, the flywheel is subjected to a constant rpm. The objective of present work is to design and optimize the flywheel for the best material. The flywheel is modeled with solid 95 (3-D element), the modeled analyses using free mesh. The FEM mesh is refined subject to convergence criteria. Preconditioned conjugate gradient method is adopted during the solution and for deflections. Von-misses stress for both materials (mild steel and mild steel alloy) are compared, the best material is suggested for manufacture of flywheel. [4] Sushama G Bawane, A. P.Ninawe and S. K.Choudhary By using optimization technique various parameter like material, cost for flywheel can be optimized and by applying an approach for modification of various working parameter like efficiency, output, energy storing capacity, we can compare the result with existing flywheel result. Based on the dynamic functions, specifications of the system the main features of the flywheel are initially determined; the detail design study of flywheel is done. Then FEA analysis for more and more designs in diverse areas of engineering is being analyzed through the software. FEA provides the ability to analyze the stresses and displacements of a part or assembly, as well as the reaction forces other elements are to impose. This thesis guides the path through flywheel design, and analysis the material selection process. The FEA model is described to achieve a better understanding of the mesh type, mesh size and boundary conditions applied to complete an effective FEA model. At last the design objective could be simply to minimize cost of flywheel by reducing material. [5] Mofid Mahdi the consumption of energy is increasing drastically. The available resources of energy are limited therefore; the search of new sources is a vital issue. This has to be done with efficient energy consumption and saving. A flywheel may provide a mechanical storage of kinetic energy. S. M. Dhengle, Dr. D. V. Bhope, S. D. Khamankarthere is many causes of flywheel failure. Among them, maximum tensile and bending stresses induced in the rim and tensile stresses induced in the arm under the action of centrifugal forces are the main causes of flywheel failure. Hence in this work evaluation of stresses in the rim and arm are studied using finite element method and results are validated by analytical calculations.the models of flywheel having four, six and eight no. arms are developed for FE analysis. The FE analysis is carried out for different cases ofloading applied on the flywheel and the maximum Von misesstresses and deflection in the rim are determined. 52 P a g e

4 From this analysis it is found that Maximum stresses induced are in the rim and arm junction. Due to tangential forces, maximum bending stresses occurs near the hub end of the arm. It is also observed that for low angular velocity the effect gravity on stresses and deflection of rim and arm is predominant. [7] D.Y. Shahare, S. M. ChoudharyThis study solelyfocuses on exploring the effects of flywheel geometry on its energy storage/deliver capability per unit mass, further defined as specific energy. In this paper we have studied various profiles of flywheel and the stored kinetic energy is calculated for the respective flywheel.various profiles designed are solid disk, disk rim,webbed/section cut, arm/spoke flywheel. It shows that smart design of flywheel geometry could both have a significant effect on the Specific Energy performance and reduce the operational loads exertedon the shaft/bearings due to reduced mass at high rotational speeds. Efficient flywheel design used to maximize the inertia of moment for minimum material used and guarantee high reliability and long life. FE analysis is carried out for different cases of loading on the flywheel and maximum von-misesstresses and total deformation are determined.(8) III PROBLEM DEFINITION Study of existing flywheel and calculation of energy requirement for the operations carried out on the 50 ton power press. The existing flywheel is more bulky and it the material cost is high. Hence in this thesis we are optimizing the flywheel design by reducing the moment of inertia i.e. the reduction of weight of flywheelby keeping the reduction ratio constant. IV SOLUTION Flywheel profiles for 50ton power press are designed such as solid disk, disk rim, webbed/section cut, arm/spoke flywheel. It shows that smart design of flywheel geometry could both have a significant effect on the Specific Energy performance and reduce the operational loads exerted on the shaft/bearings due to reduced mass at high rotational speeds. Efficient flywheel design used to maximize the inertia of moment for minimum material used and guarantee high reliability and long life. V METHODOLOGY The two main tools used in this thesis during the design of the c flywheel and also the machine in large is Ansys and Unigraphics. Ansys is used for trying out different analytical expressions in order to describe the different stresses acting on the flywheel. Unigraphics is then used to verify the results from Ansys and fine tune the design using the built in FEM module. Additionally, Unigraphics was also used to make all computer generated pictures of the flywheel present in this thesis, as well as all the drawings of the machine. 53 P a g e

5 MATHEMATICAL CALCULATION OF EXISITING FLYWHEEL:- Given data, Motor specifications:- 8HP Motor & Revolution1000 RPM, Stroke length (L)=0.200 m =200mm. Power consumption=8 x 746 =5.968 x 10 3 kw, of motor. Fig 1. Actual Flywheel P= Therefore, Torque= =57.00Nm Speed ratio calculation, Diameter of pulley (Motor)=150 mm Diameter of flywheel=790 mm Speed Reduction= =5.26 Work done per cycle, =2 x π x T x speed reduction x conversion factor = 2 x π x 57 x 5.26x0.08 = Nm x 0.08 = Nm Net Work done= power x stroke length xconversion factor = 80 x 10 3 x 0.2 x 0.35 (STD data from manufacturer) 54 P a g e

6 = 5600 Nm = Nm K.E. stored in flywheel l= Flywheel Moment of Inertia actually, K.E. = I x 2π x C s, where C s =0.02 & 2πN=ω I= = =24.84 Kgm 2 Now, practically used flywheel Moment of Inertia Weight of flywheel=409 Kg Radius of shaft R1=43 mm Outer diameter of flywheel=790 Radius=395 mm I = mk 2, where k 2 = = =32.28 kg m 2 Hence Excess Moment of Inertia= = 7.4 kg m 2 Hence keeping all dimension same, The net mass reduction in existing flywheel will be given as below As calculated 55 P a g e

7 mk 2 = 7.4 kg m 2 therefore, m= Mass f Reduction=94.82 kg But considering( factor of safty) FOS= 1.2 Net mass reduction= = kg Net mass reduction=79.00 kg from existing flywheel. % reduction in mass of flywheel = x 100 =19.32% Hence it is proved that the existing flywheel have excess weight. The excess weight is kg and it can be reduced without affecting the performance of flywheel and keeping the stress values same. Existing Flywheel Of machine in unigraphics. Experimental Result S/N Ratio For Plate Type Flywheel Minitab Results 56 P a g e

8 VI ANSYS RESULT Deformation Loading Meshing Principle Stresses Shear Stress Strain Energy 57 P a g e

9 VII CONCLUSION From the study it has been concluded that the weight of existing flywheel is kg and the energy stored in flywheel is N-m which is 21 % more than it required for the application of 50 Ton Power press Machine Flywheel. So in this study the weight of Flywheel is optimized and it has been found reduction up to kg for plate type is almost get reduced by % and energy stored is N-m which is sufficient for the current application under study i.e. 50 Ton power press machine Flywheel. REFERENCES 1. Akshay P. Punde, G.K.Gattani, Analysis of Flywheel, InternationalJournal of Modern Engineering Research (IJMER), Vol.3, Issue.2,March-April pp Bjorn Bolund, Hans Bernhoff, Mats Leijon, Flywheel energy andpower storage systems,international journal of Renewable andsustainable Energy Reviews 11 (2007) SudiptaSaha, Abhik Bose, G. SaiTejesh, S.P. Srikanth, computeraided design & analysis on flywheel for greater efficiency,international Journal of Advanced Engineering Research and Studies,IJAERS/Vol. I/ Issue II/January-March, 2012/ M.lavakumar, R.prasannasrinivas, Design and analysis of lightweight motor vehicle flywheel, International Journal of ComputerTrends and Technology (IJCTT) volume 4 Issue -7July Sushama G Bawane, A P Ninawe and S K Choudhary, Analysis andoptimization of flywheel, International Journal of mechanicalengineering and robotics Vol. 1, No. 2, July S. M. Dhengle, Dr. D. V. Bhope, S. D. Khamankar, Investigation ofstresses in arm type rotating flywheel, International Journal ofengineering Science and Technology (IJEST), Vol. 4 No.02 February D.Y. Shahare, S. M. Choudhary, Design Optimization of Flywheel ofthresher using FEM, Advanced Materials Manufacturing &Characterization Vol3 Issue 1 (2013) [8]. M. Lavakumar, Design and analysis of light weight Motor vehicle flywheel International Journal of Computer Trends andtechnology (IJCTT) volume 4 Issue 7 July S. Saha Computer aided design & analysis on flywheel for greater efficiency International Journal of dvanced EngineeringResearch and Studies E-ISSN A Test book on Machine Design by R.S.Khurmi&J.K.Gupta, Eurosia publishing house, PVT, LTD, Ram Nagar, New Delhi Finite Elements in Engineering By Tirupathi R. Chandrupatla& Ashok D. Belegundu,ThirdEdition,PHI Learning PVT.LTD.New Delhi110001, Machine Design by B.D.Shiwalkar.[9]. Dr. P. C. Sharma and Dr. D. K. Agarwal, Machine Design, millennium edition, pp P a g e